Question

10. The cost of a book is 12 more than 3 times the cost of a copy. The sum of their cost is 72.
Find their cost.​

Answer 1

Answer:

Let the cost of notebook be x, then

let the cost of book be 3x

3x + 12 = 72

3x = 72 - 12

3x = 60

x = 60 ÷ 3

x = 20

Answer 2

Answer:

Hope you can understand it easily.......................

Step-by-step explanation:

-/ Let's take the cost of a copy as X.......

-/ Then cost of a book will be = ( 12 + 3X )

Here, According to the question. ..........

Cost of a book+Cost of a copy= 72

-> (12 + 3X) + X = 72

Or , 4X = 72 - 12

Or , 4X = 60

Or , X = 60/4

Or , X = 15

Hence , Cost of one copy is Rupees 15

And cost of a book will be

= ( 12 + 3X )

= 12 + (3×15)

= 12 + 45

= 47 ( Rupees )

Therefore, Cost of a book will be 47 Rupees and cost of a copy will be 15 Rupees.